The pinna enhances angular discrimination in the frontal hemifield.
Level 3 - non-randomized controlled study
Controlled laboratory psychoacoustic and acoustic experiment with within-subject manipulations
PubMed 36319254 · doi:10.1121/10.0014599
What was done
Psychoacoustic experiments assessed horizontal sound angular discrimination during binaural listening with intact pinna cues, acoustically bypassed pinna cues, and low-pass filtered audio. In addition, physical acoustic measurements evaluated spectral changes induced by the pinna across sound source azimuths from 0° to 90°.
What was found
The abstract reports no numerical values, sample sizes, or test statistics. The presence of the pinna improved horizontal sound discrimination in the frontal hemifield compared to the rear hemifield, especially for directions away from the median plane. Acoustically bypassing the pinna or low-pass filtering abolished the frontal advantage while leaving rear discrimination unaffected. Acoustic measurements showed a pinna-dependent spectral prominence that shifted smoothly in frequency across azimuth angles from 0° to 90°.
Why it matters
This study demonstrates that horizontal sound localization relies on more than just binaural timing and level cues, showing that high-frequency pinna spectral cues directly enhance horizontal discrimination in the frontal field.
Limits
The abstract provides no sample size, participant characteristics, stimulus specifications, or quantitative metrics (such as angular discrimination thresholds or effect sizes). Results reflect controlled laboratory conditions and may not directly generalize to reverberant or multi-talker real-world environments.